Application of ISCST3 model on air environmental impact assessment of the Xishan Tunnel Project

Based on traffic planning of year 2020 in the Haidian District, Beijing, vehicle emission lists were established for main roads in the Xishan mountain area. Industrial Source Complex Short-Term Version 3 (ISCST3) model was applied to simulate temporal and spatial distribution of vehicle emissions (CO and NO_x) of the Xishan Tunnel Project related area, and emission impacts on the Xishan Mountain area, which including the 5^th Ring Road adjacent area of the Fragrant Hill and northern area of the Haidian District, were analyzed and compared considering planned traffic conditions with and without the Xishan Tunnel construction. The results show that the Xishan Tunnel construction will alleviate vehicle emission pollution along the Badaling Highway, the West Road of YuanMingYuan, and west segment of the 5th Ring Road, and worsen the emission pollution along the Shangzhuan Road and its southern-extended segment. However, impact of vehicle emission on Beijing Arboretum in the Fragrant Hill area is not significant with the Xishan Tunnel construction.